IL-25 and intra peritoneal transfer of ILC2s increase splenic B1a cells in <i>Apoe</i>^<i>-/-</i> mice.

<p><b>A</b>) Gating strategy to identify splenic B1a cells, gated as CD19⁺B220^lowCD11b⁺CD5⁺IgM⁺ with flow cytometry. <b>B</b>) Splenic B1a cells in <i>Apoe</i>^<i>-/-</i> mice treated for one week (11–12 weeks of age) with 1μg rmIL-25 per day or equal volume of the control medium. <b>C</b>) FACS sorted ILC2s (Lin^-CD45⁺IL17RB⁺ICOS⁺IL7ra^intermediate) from the spleens of IL-25-treated <i>Apoe</i>^<i>-/-</i> mice were expanded <i>in vitro</i> and transferred i.p. into young <i>Apoe</i>^<i>-/-</i> mice (day 0). Controls were given the same volume of PBS. On day 3, mice were killed, spleens were dissected and analyzed by flow cytometry for B1a cells. <b>D</b>) Splenic B1a cells in <i>IL-5</i>^<i>-/-</i> mice treated for one week (11–12 weeks of age) with 1μg rmIL-25 per day or equal volume of the control medium. Each dot in the figure represents one mouse and the bar the median value. *<i>P</i><0.05.